This study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic temperatures.First,the small-signal nonlinear model of the transistor at hi...This study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic temperatures.First,the small-signal nonlinear model of the transistor at high frequency at 5 K is analyzed using quantum theory,and the related Lagrangian is theoretically derived.Subsequently,the total quantum Hamiltonian of the system is derived using Legendre transformation.The Hamiltonian of the system includes linear and nonlinear terms by which the effects on the time evolution of the states are studied.The main result shows that the squeezed state can be generated owing to the transistor’s nonlinearity;more importantly,it can be manipulated by some specific terms introduced in the nonlinear Hamiltonian.In fact,the nonlinearity of the transistors induces some effects,such as capacitance,inductance,and second-order transconductance,by which the properties of the external oscillators are changed.These changes may lead to squeezing or manipulating the parameters related to squeezing in the oscillators.In addition,it is theoretically derived that the circuit can generate two-mode squeezing.Finally,second-order correlation(photon counting statistics)is studied,and the results demonstrate that the designed circuit exhibits antibunching,where the quadrature operator shows squeezing behavior.展开更多
We fabricated a set of symmetric gate-recess devices with gate length of 70 nm.We kept the source-to-drain spacing(L_(SD))unchanged,and obtained a group of devices with gate-recess length(L_(recess))from 0.4µm to...We fabricated a set of symmetric gate-recess devices with gate length of 70 nm.We kept the source-to-drain spacing(L_(SD))unchanged,and obtained a group of devices with gate-recess length(L_(recess))from 0.4µm to 0.8µm through process improvement.In order to suppress the influence of the kink effect,we have done SiN_(X) passivation treatment.The maximum saturation current density(ID_(max))and maximum transconductance(g_(m,max))increase as L_(recess) decreases to 0.4µm.At this time,the device shows ID_(max)=749.6 mA/mm at V_(GS)=0.2 V,V_(DS)=1.5 V,and g_(m,max)=1111 mS/mm at V_(GS)=−0.35 V,V_(DS)=1.5 V.Meanwhile,as L_(recess) increases,it causes parasitic capacitance C_(gd) and g_(d) to decrease,making f_(max) drastically increases.When L_(recess)=0.8µm,the device shows f_(T)=188 GHz and f_(max)=1112 GHz.展开更多
With the widespread utilization of indium-phosphide-based high-electron-mobility transistors(InP HEMTs)in the millimeter-wave(mmW)band,the distributed and high-frequency parasitic coupling behavior of the device is pa...With the widespread utilization of indium-phosphide-based high-electron-mobility transistors(InP HEMTs)in the millimeter-wave(mmW)band,the distributed and high-frequency parasitic coupling behavior of the device is particularly prominent.We present an InP HEMT extrinsic parasitic equivalent circuit,in which the conductance between the device electrodes and a new gate-drain mutual inductance term L_(mgd)are taken into account for the high-frequency magnetic field coupling between device electrodes.Based on the suggested parasitic equivalent circuit,through HFSS and advanced design system(ADS)co-simulation,the equivalent circuit parameters are directly extracted in the multi-step system.The HFSS simulation prediction,measurement data,and modeled frequency response are compared with each other to verify the feasibility of the extraction method and the accuracy of the equivalent circuit.The proposed model demonstrates the distributed and radio-frequency behavior of the device and solves the problem that the equivalent circuit parameters of the conventional InP HEMTs device are limited by the device model and inaccurate at high frequencies when being extracted.展开更多
文摘This study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic temperatures.First,the small-signal nonlinear model of the transistor at high frequency at 5 K is analyzed using quantum theory,and the related Lagrangian is theoretically derived.Subsequently,the total quantum Hamiltonian of the system is derived using Legendre transformation.The Hamiltonian of the system includes linear and nonlinear terms by which the effects on the time evolution of the states are studied.The main result shows that the squeezed state can be generated owing to the transistor’s nonlinearity;more importantly,it can be manipulated by some specific terms introduced in the nonlinear Hamiltonian.In fact,the nonlinearity of the transistors induces some effects,such as capacitance,inductance,and second-order transconductance,by which the properties of the external oscillators are changed.These changes may lead to squeezing or manipulating the parameters related to squeezing in the oscillators.In addition,it is theoretically derived that the circuit can generate two-mode squeezing.Finally,second-order correlation(photon counting statistics)is studied,and the results demonstrate that the designed circuit exhibits antibunching,where the quadrature operator shows squeezing behavior.
基金the National Natural Science Foundation of China(Grant No.61434006).
文摘We fabricated a set of symmetric gate-recess devices with gate length of 70 nm.We kept the source-to-drain spacing(L_(SD))unchanged,and obtained a group of devices with gate-recess length(L_(recess))from 0.4µm to 0.8µm through process improvement.In order to suppress the influence of the kink effect,we have done SiN_(X) passivation treatment.The maximum saturation current density(ID_(max))and maximum transconductance(g_(m,max))increase as L_(recess) decreases to 0.4µm.At this time,the device shows ID_(max)=749.6 mA/mm at V_(GS)=0.2 V,V_(DS)=1.5 V,and g_(m,max)=1111 mS/mm at V_(GS)=−0.35 V,V_(DS)=1.5 V.Meanwhile,as L_(recess) increases,it causes parasitic capacitance C_(gd) and g_(d) to decrease,making f_(max) drastically increases.When L_(recess)=0.8µm,the device shows f_(T)=188 GHz and f_(max)=1112 GHz.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61434006 and 61704189)the Fund from the Youth Innovation Promotion Association of the Chinese Academy of Sciences。
文摘With the widespread utilization of indium-phosphide-based high-electron-mobility transistors(InP HEMTs)in the millimeter-wave(mmW)band,the distributed and high-frequency parasitic coupling behavior of the device is particularly prominent.We present an InP HEMT extrinsic parasitic equivalent circuit,in which the conductance between the device electrodes and a new gate-drain mutual inductance term L_(mgd)are taken into account for the high-frequency magnetic field coupling between device electrodes.Based on the suggested parasitic equivalent circuit,through HFSS and advanced design system(ADS)co-simulation,the equivalent circuit parameters are directly extracted in the multi-step system.The HFSS simulation prediction,measurement data,and modeled frequency response are compared with each other to verify the feasibility of the extraction method and the accuracy of the equivalent circuit.The proposed model demonstrates the distributed and radio-frequency behavior of the device and solves the problem that the equivalent circuit parameters of the conventional InP HEMTs device are limited by the device model and inaccurate at high frequencies when being extracted.
基金Supported by National Natural Science Foundation of China(11775191,61404115,61434006)Development Fund for Outstanding Young Teachers in Zhengzhou University China(1521317004)
